Infections Flashcards
CMV - IgM + - what % have infection?
25%
Can persist for months after primary infection, and recur with reactivation
Symptoms primary CMV
Usually asymptomatic
May have a viral illness
Risk factors for CMV acquisition
Child care workers (12% seroconversion/y)
parents with children in day are
CMV general population seroconversion
2%/y
Prenatal diagnostic testing
Amnio for CMV PCR
at least 6 weeks after primary infection
Sensitivity ~100% >21/40
USS low sensitivity and specificity `
USS features of CMV
Microcephaly Ascites Oligo/poly Abdominal/intracranial calcification hydrocephalus Hydrops IUGR Hepatomegaly
Prevention of CMV transmission
- No role of IVIG in prevention
Management of confirmed foetal CMV infection
- TOP, with the knowledge it is difficult to predict the severity of infection based on PCR and USS
- IVIG - better clinical outcomes for babies at 1 year in one non-randomised trial
CMV - risk of transmission with seroconversion
- risk of symptomatic CMV
- risk of sequelae
30%
- with transmission: (overall 10-20% risk long term squeal of congenitally infected child)
- 10% symptomatic > 50% sequelae
- 90% asymptomatic > 10% sequelae
Clinical signs of symptomatic CMV
- high early mortality
- microphaly
- seizures
- chorioretinitis
- developmental delay
- sensorineural hearing loss
Newborn Ix for CMV
- Examination
- Serology
- Urine/salive PCR
> if + then opthal and radiological (USS and MRI)
> Rx w oral valganciclovir
Practices for reducing infection with CMV
- Assume children <3y in your care have CMV
- Thoroughly wash hands with soap and water after touching child/toys/nappies/feeding/bathing etc
- Don’t share cups, plates, utensils, toothbrushes or food
- Do not kiss the child on or near the mouth
- Do not share a bed w the child
- Do not share towels or washcloths
Prevalence rubella
1/100 000 pregnancies
Symptom rubella infection
50% asymptomatic
Vague coryzal symptoms
Examthem: maculopapular, face>trunk, resolves face>trunk
+/- polyarthralgia
+/- tender lymphadenopathy
Forchemers spots (rose like) on soft palate
Diagnosis of rubella infection
4x increase in IgG titre (usually 2/52)
IgM +
Culture +
Amnio/CVS PCR
Diagnosis of neonatal congenital rubella infection
IF IgM + at birth > retest 1/12
Infant Rubella IgG higher for longer than expected (maternal IgG lasts ~6/52)
Chance of foetal infection across gestations (Rubella)
T1 80%
T2 30%
T3 100%
Congenital rubella infection vs congenital rubella syndrome
Infection: - MC - SB - Birth defects - Asymptomatic - IUGR Syndrome: = constellation of birth defects - hearing impairment - congenital heart defect - cataracts/glaucoma - pigmentary retinopathy
Rx rubella in pregnancy
Prevention - vaccine prepreg
Supportive care
Rx of complications e.g. steroids for thrombocytopenia
Manage the foetus: discuss TOP (esp <16/40), no direct in utero Rx
Manifestations of congenital infection EARLY
- Hearing loss 60%
- Heart defects 45% (PDA, pulmonary stenosis)
- Microcephaly 25%
- Cataracts 25%
- IUGR 25%
- hepatosplenomegaly/jaundice/purpura/pneumonitis
- meningoencephalitis
Manifestations of congenital rubella infection LATE
- Hearing loss
- Intellectual disability
- DM
- Thyroid dysfn
- Progressive pan-encephalitis
- Immune defects
Neonatal follow up after rubella infection
- Clinical attendants at birth should be rubella immune
- IX: IgM, Urine PCR, culture urine and throat swab (can take weeks)
- Opthal, cardiac and hearing assessments at birth
- Regular clinical assessment
- May be infectious for 1y of life
Risk of congenital defects by gestational age (Rubella)
T1 ~85%
13-16/40 ~35%
>16/40 - rare
HSV seroprevalence
HSV 1= 60%
HSV 2 = 20%